package com.wectrls.security;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.commons.codec.binary.StringUtils;
import org.bouncycastle.util.encoders.Base64;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.core.Authentication;
import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.security.oauth2.common.exceptions.UnapprovedClientAuthenticationException;
import org.springframework.security.oauth2.provider.*;
import org.springframework.security.oauth2.provider.token.AuthorizationServerTokenServices;
import org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler;
import org.springframework.stereotype.Component;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;

/**
 * @ClassName AuthenticationSuccessHandler
 * @Description //TODO 用户验证成功处理器
 * @Author 陈建
 * @Date 2019/2/19 11:15
 * @Version 2.0
 */
@Component
public class CustomAuthenticationSuccessHandler extends SavedRequestAwareAuthenticationSuccessHandler {
    @Autowired
    private ObjectMapper objectMapper;

    @Autowired
    private ClientDetailsService clientDetailsService;

    @Autowired
    private AuthorizationServerTokenServices authorizationServerTokenServices;

    @Override
    public void onAuthenticationSuccess(HttpServletRequest request,
                                        HttpServletResponse response,
                                        Authentication authentication) throws IOException, ServletException {
        String header = request.getHeader("Authorization");
        header = null != header ? header : request.getHeader("authorization");
        if (header == null || !header.startsWith("Basic ")) {
            throw new UnapprovedClientAuthenticationException("请求头中无client信息");
        }

        String[] tokens = extractAndDecodeHeader(header, request);
        assert tokens.length == 2;
        String clientId = tokens[0];
        String clientSecret = tokens[1];

        ClientDetails clientDetails = clientDetailsService.loadClientByClientId(clientId);

        if (clientDetails == null) {
            throw new UnapprovedClientAuthenticationException("clientId对应的配置信息不存在:" + clientId);
        } else if (!StringUtils.equals(clientDetails.getClientSecret(), clientSecret)) {
            throw new UnapprovedClientAuthenticationException("clientSecret不匹配:" + clientId);
        }
        TokenRequest tokenRequest = new TokenRequest(new HashMap<>(), clientId, clientDetails.getScope(), "custom");
        OAuth2Request oAuth2Request = tokenRequest.createOAuth2Request(clientDetails);
        OAuth2Authentication oAuth2Authentication = new OAuth2Authentication(oAuth2Request, authentication);
        OAuth2AccessToken token = authorizationServerTokenServices.createAccessToken(oAuth2Authentication);
        //TODO 添加登录记录
//        String remoteAddr = request.getRemoteAddr();
//        String os = request.getHeader("User-Agent");
        String s = objectMapper.writeValueAsString(token);
        response.setContentType("application/json;charset=UTF-8");
        response.getWriter().write(s);
    }

    private String[] extractAndDecodeHeader(String header, HttpServletRequest request) throws IOException {

        byte[] base64Token = header.substring(6).getBytes("UTF-8");
        byte[] decoded;
        try {
            decoded = Base64.decode(base64Token);
        } catch (IllegalArgumentException e) {
            throw new BadCredentialsException("Failed to decode basic authentication token");
        }
        String token = new String(decoded, "UTF-8");
        int delim = token.indexOf(":");
        if (delim == -1) {
            throw new BadCredentialsException("Invalid basic authentication token");
        }
        return new String[]{token.substring(0, delim), token.substring(delim + 1)};
    }

    /*public static void main(String[] args) {

        System.out.println(new String(Base64.encode("123456:QWEasd123".getBytes())));

    }*/
}
